Yes, Great coop!- and will be even better once the windows are cut in and the chickens can see what they're doing in there! LOL
as far as planting something for them to munch...its a good IDEA but almost pointless- as someone else stated they will decimate it in one hour flat- and it will NEVER get a chance to grow back- ever! There is a barren dirt path that extends about six inches around my entire chicken fence, where the lush green yard grass was pecked into extinction.
I once spent the day digging pesky unwanted dandilions out of my step mothers front yard to transplant along MY chickens' fence.... here I was thinking I was going a grand thing- In one day the dandilions were eated down to the dirt and pecked to the point of oblivion.
Best bet for treats and stuff for entertainment...my husband and I stop (inconspicuously) whenever we see a big field with dandilions and clovers and we pick a bag full of it and take it home (break it up a bunch) and toss it in their pen. They love it. They also love slices of watermellon, cantelope, corn cob, huge cucumbers, whole tomatoes, anything you can part with. Our families always grow so many veggies they end up composting most of it, so last time we convinced them to set it aside for our birds instead of the compost pile.
They will eat everything and anything (or at least try to) they are more 'billy goat' then billy goats I think! LOL
if you have a big enough yard, you can try to allow them as much raoming space as you can as that should keep them pretty busy that way. they like to 'hunt and pick' dirt, pebbles, bugs....and roll in the dirt!
I had a outside run about 8X12 feet and once they pecked it clean they would squack out of boredom...(transplanting the dandilions didnt work LOL) so I added some extra footage on the other side (kinda gives them '2 play yards') and that has pleased them I think, when they get bored they venture over to their 'other yard' and peck around over there. LOL
silly birds!
good luck!